A ballastless track and its assembled double-track steel truss subgrade structure

Abstract

An embodiment of the present invention discloses a ballastless track and its steel truss assembled double-track subgrade structure. The steel truss assembled double-track subgrade structure includes a top plate, a bottom plate, a steel truss, and supports. The steel truss is supported between the top plate and the bottom plate. A part of the supports is installed on the convex platform on the bottom side of the top plate and connected to the top end of the steel truss, and another part of the supports is installed on the convex platform on the top side of the bottom plate and connected to the bottom end of the steel truss. This subgrade structure reduces the land area of the foundation, reduces the amount of foundation treatment work, eliminates the filling material, and reduces the construction cost; the steel truss has obvious advantages in terms of size and performance compared with reinforced concrete components; the convex platform increases the ability to bear the load transmitted by the steel truss; the cross-section is an inverted trapezoid, and the width of the bottom plate is smaller than the width of the top plate, making the structure more stable; the steel truss is arranged in a triangular grid, effectively transmitting the upper load and reducing the structural weight, reducing the requirement for the bearing capacity of the foundation; each component can be prefabricated and assembled, facilitating construction and quality control, and convenient for operation and maintenance.

Description

Technical Field

[0001] This application relates to the field of track technology, and particularly to a ballastless track and its steel truss assembled double-track subgrade structure. Background Art

[0002] The standard form of the traditional filler subgrade for high-speed railways is a trapezoidal cross-section. Generally, a certain slope is adopted below the shoulder elevation. From top to bottom, it is the subgrade surface layer, the subgrade bottom layer, and the subgrade body. The track structure is laid above the subgrade surface layer, and the foundation is treated below the subgrade body. This form often has a large floor area, a wide foundation treatment range, and a high demand for fillers. At the same time, in recent years, with the strong promotion of high-speed railway construction in China, the coverage area of the high-speed railway network has been continuously expanding. However, in some special areas, the construction of high-speed railway subgrades is restricted by various external factors and is often difficult to implement smoothly. On the one hand, affected by local urban development and land planning, the problem of limited railway construction land scope gradually appears in some areas, and it is difficult to meet the land use restriction requirements by using the traditional trapezoidal filler subgrade form; on the other hand, under the unfavorable conditions such as lack of fillers in plain areas, local fillers cannot meet the construction requirements of high-speed railway subgrades, while the purchased fillers increase the transportation distance, which not only consumes the construction period but also increases the investment.

[0003] In response to the above problems, the subgrade engineering field has tried various modified forms on the basis of the traditional filler subgrade, such as the trough-shaped structure subgrade, the high-pile cap pile-slab structure subgrade, etc. Although it has improved in reducing the floor area, the demand for high-quality fillers is still large, and it still restricts the implementation of subgrade engineering in plain areas lacking fillers. In addition, whether it is the trough-shaped structure subgrade or the high-pile cap structure subgrade, a large amount of reinforced concrete structures are used, which not only increases the construction difficulty but also further increases the weight of the subgrade itself, requires a higher foundation, leads to an increase in the foundation treatment workload, and an increase in investment.

[0004] Therefore, there is an urgent need for a new type of subgrade form to reduce land use and filler demand and save investment on the premise of ensuring that the construction quality meets the safe operation of railways. Summary of the Invention

[0005] In view of this, the embodiments of this application expect to provide a ballastless track and its steel truss assembled double-track subgrade structure to achieve the purpose of reducing the subgrade land area and reducing the subgrade filler demand.

[0006] To achieve the above object, the technical solution of the embodiments of this application is realized as follows:

[0007] An embodiment of the present invention provides a precast double-track subgrade structure with steel trusses for ballastless tracks. The subgrade structure includes a top plate, a bottom plate, at least two steel trusses, and a plurality of bearings. The steel trusses are arranged at intervals along the width direction of the subgrade structure and are supported between the top plate and the bottom plate. The width of the top plate is greater than that of the bottom plate, and the two are parallel and centered. Some of the bearings are fixedly installed on the bottom side of the top plate and are fixedly connected to the top ends of the corresponding steel trusses. The other part of the bearings are fixedly installed on the top side of the bottom plate and are fixedly connected to the bottom ends of the corresponding steel trusses. The top plate, the bottom plate, the steel trusses, and the bearings are all precast components. The top end of the steel truss is detachably connected to the corresponding bearing; the bottom end of the steel truss is detachably connected to the corresponding bearing; the top plate is detachably connected to the corresponding bearing; the bottom plate is detachably connected to the corresponding bearing.

[0008] In some embodiments, the steel trusses are arranged in pairs along the width direction of the subgrade structure, and the distance between the positions where the two paired steel trusses are connected to the top plate is greater than the distance between the positions where they are connected to the bottom plate.

[0009] In some embodiments, a first boss is provided on the bottom side of the top plate. The first boss is provided with a first bearing mounting surface. The projection of the first bearing mounting surface on the cross-section in the width direction of the subgrade structure is inclined to the horizontal direction, and the formed inclination angle is the first inclination angle. The bearings located on the bottom side of the top plate are fixedly installed on the first bearing mounting surface; a second boss is provided on the top side of the bottom plate. The second boss is provided with a second bearing mounting surface. The projection of the second bearing mounting surface on the cross-section in the width direction of the subgrade structure is inclined to the horizontal direction, and the formed inclination angle is the second inclination angle. The bearings located on the top side of the bottom plate are fixedly installed on the second bearing mounting surface.

[0010] In some embodiments, the slopes of the first inclination angle and the second inclination angle are equal.

[0011] In some embodiments, the steel trusses are perpendicular to the first bearing mounting surface and the second bearing mounting surface.

[0012] In some embodiments, the slope of the first inclination angle is 1:4; and / or, the slope of the second inclination angle is 1:4.

[0013] In some embodiments, the thickness of the top plate in the area where the first boss is located is 550 mm - 650 mm, and the thickness of the top plate in the area outside the first boss is 450 mm - 550 mm.

[0014] In some embodiments, the thickness of the bottom plate in the area where the second boss is located is 750 mm - 850 mm, and the thickness of the bottom plate in the area outside the second boss is 1050 mm - 1150 mm.

[0015] An embodiment of the present invention further provides a ballastless track, which includes the steel truss assembled double-track subgrade structure of any one of the foregoing ballastless tracks, as well as a track slab foundation, a track slab, and rails. The track slab foundation, the track slab, and the rails are sequentially arranged from bottom to top on the top surface of the top plate.

[0016] In the steel truss assembled double-track subgrade structure of the ballastless track involved in the embodiment of the present invention, the problems of limited construction land for high-speed railway subgrades and lack of fillers in plain areas are solved. Compared with traditional filler subgrades, not only the land area is reduced, but also the amount of foundation treatment work is further reduced, saving investment; in addition, the structure itself does not require any fillers, solving the problem of lack of fillers in plain areas; the subgrade structure involved is a combined structure of reinforced concrete and steel trusses, and the upper load is borne by the top plate and transmitted to the bottom plate and the foundation through the steel trusses and bearings. As load-bearing components, the steel trusses have obvious advantages in terms of size and performance compared with reinforced concrete components; the bosses increase the ability to bear the load transmitted by the steel trusses; the cross-section is trapezoidal in reverse, and the width of the bottom plate is smaller than that of the top plate, making the structural framework more stable; the steel trusses are arranged in a triangular grid, effectively transmitting the upper load and minimizing the structural weight, reducing the requirement for the bearing capacity of the foundation; the top plate, the bottom plate, the steel trusses, and the bearings are all independent structures, connected by fixing bolts, and can be prefabricated and assembled, facilitating construction and quality control, and being convenient for operation and maintenance. This subgrade structure can be widely applied to the construction of high-speed railway subgrades in areas with limited land use or lack of fillers. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a cross-sectional schematic diagram of a ballastless track according to an embodiment of the present invention;

[0018] Figure 2 is Figure 1 the right view of, in which, the track foundation plate 9, the track slab 10, and the rails 11 are omitted;

[0019] Figure 3 is Figure 2 a partial schematic diagram at the K-type bearing in;

[0020] Figure 4 is Figure 2 a partial schematic diagram at the V-type bearing in;

[0021] Figure 5 is Figure 2 a partial schematic diagram at the single-type bearing in.

[0022] DESCRIPTION OF THE REFERENCE NUMERALS

[0023] 1. Top plate 2. First boss 21. First support mounting surface

[0024] 3. Bottom plate 4. Second boss 41. Second support mounting surface

[0025] 5. Steel truss 6. K-type support 61. K-type support mounting plate

[0026] 62. Second steel truss interface 63. Third steel truss interface 7. V-type support

[0027] 71. V-type support mounting plate 72. Fourth steel truss interface 73. Fifth steel truss interface

[0028] 8. Single-type support 81. Single-type support mounting plate 82. First steel truss interface

[0029] 9. Track slab foundation 10. Track slab 11. Rail Detailed implementation manners

[0030] It should be noted that, without conflict, the embodiments and technical features in the embodiments of the present application can be combined with each other. The detailed description in the specific implementation manners should be understood as an explanatory illustration of the purpose of the present application and should not be regarded as an improper limitation to the present application.

[0031] In the description of the embodiments of the present application, "upper", "lower", "width direction", orientation or positional relationship are based on the Figure 1 orientation or positional relationship shown in the Figure 1 . The left and right directions in the

[0032] are the "width direction". It should be understood that these orientation terms are only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present application. Figure 1 The embodiments of the present invention provide a steel truss assembled double-track subgrade structure for ballastless tracks. Referring to

[0033] In the subgrade structure in the embodiments of the present invention, since the width of the top plate 1 is greater than the width of the bottom plate 3, the occupied area of the subgrade structure is smaller than that of the traditional subgrade structure, solving the problem of limited construction land for high-speed railway subgrades. At the same time, a frame structure composed of steel trusses 5, top plate 1 and bottom plate 3 is adopted, reducing the amount of foundation treatment work and eliminating the need for traditional subgrade fillers, solving the problem of lack of fillers in plain areas and saving investment. In addition, the steel trusses 5 are fixedly connected to the bearings, the bearings to the top plate 1, and the bearings to the bottom plate 3. The structure is simple, easy to construct and maintain later. As a force-transmitting component, the steel trusses 5 have obvious advantages in terms of size and performance compared with the reinforced concrete components used in traditional structures.

[0034] The steel trusses 5 can be arranged in the form of one pair or multiple pairs along the width direction of the subgrade structure, and are arranged between the top plate 1 and the bottom plate 3 in a vertical or inclined manner. In the embodiments of the present invention, the number of steel trusses 5 is two, and they are arranged in an inclined pair along the width direction of the subgrade structure, that is, the distance between the positions where the paired two steel trusses 5 are connected to the top plate 1 is greater than the distance between the positions where the paired two steel trusses 5 are connected to the bottom plate 3, making the steel trusses 5 in an inverted trapezoid shape in the cross-section, and the structural framework is more stable. At the same time, on the premise of meeting the structural strength requirements, the number of steel trusses 5 in the cross-section is one pair, simplifying the structure and reducing the cost.

[0035] To further improve the load conduction effect of the steel trusses, the structures of the top plate 1 and the bottom plate 3 can be optimized. In one embodiment, referring to Figure 1 , a first boss 2 is provided on the bottom side of the top plate 1, the first boss 2 is provided with a first bearing mounting surface 21, and the projection of the first bearing mounting surface 21 in the cross-section along the width direction of the subgrade structure is inclined to the horizontal direction, and the formed inclination angle is the first inclination angle θ. The bearing located on the bottom side of the top plate 1 is fixedly installed on the first bearing mounting surface 21; a second boss 4 is provided on the top side of the bottom plate 3, the second boss 4 is provided with a second bearing mounting surface 41, and the projection of the second bearing mounting surface 41 in the cross-section along the width direction of the subgrade structure is inclined to the horizontal direction, and the formed inclination angle is the second inclination angle β. The bearing located on the top side of the bottom plate 3 is fixedly installed on the second bearing mounting surface 41. By providing the first boss 2, it is beneficial to concentrate the load received by the top plate 1 on the steel trusses 5, and by providing the second boss 4, the load received by the steel trusses 5 can be better dispersed to the bottom plate 3, thereby increasing the ability to bear the load transmitted by the steel trusses.

[0036] For the convenience of standardized design, reducing quality control and construction process flows, in some embodiments, the first inclination angle θ and the second inclination angle β can be set to be equal.

[0037] In one embodiment, the steel truss 5 is vertically installed with respect to the first support mounting surface 21 and the second support mounting surface 41, thereby optimizing the load transfer capacity of the steel truss 5 and further enhancing the overall structural strength and load-bearing capacity.

[0038] In one embodiment, along the length direction of the subgrade structure, a plurality of first bosses 2 are arranged at intervals on the bottom side of the top plate, and one or more supports are arranged on each first boss; and / or, a plurality of second bosses are arranged at intervals on the fixed side of the bottom plate, and one or more supports are arranged on each second boss. In another embodiment, refer to Figure 2 , the first boss 2 continuously extends along the length direction of the subgrade structure, and a plurality of supports are arranged on the first support mounting surface 21; and / or, the second boss 4 continuously extends along the length direction of the subgrade structure, and a plurality of supports can be installed at intervals along the length direction on the second support mounting surface 41; in this way, the manufacturing and construction processes can be simplified, and the construction workload can be reduced.

[0039] The steel truss 5 can be arranged such that each steel rod is independent and vertically arranged along the length direction of the subgrade structure, or can be in the form of a frame structure formed by combining multiple steel rods and arranged in a triangular grid along the length direction of the subgrade structure as adopted in this embodiment. Refer to Figure 2 , that is, multiple steel rods are installed obliquely with respect to the vertical direction, and are arranged in a triangle at the connection of adjacent two steel rods, which can effectively transfer the upper load. While enhancing the structural strength, the structural weight is minimized to the greatest extent, and the requirement for the bearing capacity of the foundation is reduced.

[0040] In some embodiments, in order to facilitate the combination of the steel truss 5 into a frame structure and arrange it in a triangular grid, the brackets can be prefabricated into different shapes. In this embodiment, refer to Figure 2 , according to the shape of the support, it can be divided into a K-shaped support 6, a V-shaped support 7, and a single-type support 8. Among them, please refer to Figure 5 , the single-type support 8 includes a single-type support mounting plate 81 and a first steel truss interface 82. The first steel truss interface 82 is perpendicular to the single-type support mounting plate 81. The single-type support mounting plate 81 is attached to and fixedly connected to the first support mounting surface 21 or the second support mounting surface 41, for example, by screw connection; one end of the steel rod is inserted into the first steel truss interface 82 and fixedly connected therein, for example, by screw connection. The single-type support 8 is suitable for fixedly connecting one steel rod.

[0041] Please refer to Figure 3, the K-shaped support 6 includes a K-shaped support mounting plate 61, a second steel truss interface 62 perpendicular to the K-shaped support mounting plate 61, and a third steel truss interface 63 inclined to the K-shaped support mounting plate 61. The K-shaped support mounting plate 61 is attached to and fixedly connected to the first support mounting surface 21 or the second support 41 mounting surface, for example, by screw connection. One end of a steel rod is inserted into the second steel truss interface 62 and fixedly connected therein, for example, by screw connection. One end of another steel rod is inserted into the third steel truss interface 63 and fixedly connected therein, for example, by screw connection. The K-shaped support 6 is suitable for fixedly connecting two steel rods.

[0042] Please refer to Figure 4 , the V-shaped support 7 includes a V-shaped support mounting plate 71, a fourth steel truss interface 72 inclined to the V-shaped support mounting plate 71, and a fifth steel truss interface 73 inclined to the V-shaped support mounting plate 71. The inclination angle between the fourth steel truss interface 72 and the V-shaped support mounting plate 71, the inclination angle between the fifth steel truss interface 73 and the V-shaped support mounting plate 71, and the inclination angle between the third steel truss interface 63 and the K-shaped support mounting plate 61 are equal. The V-shaped support mounting plate 71 is attached to and fixedly connected to the first support mounting surface 21 or the second support 41 mounting surface, for example, by screw connection. One end of a steel rod is inserted into the fourth steel truss interface 72 and fixedly connected therein, for example, by fixed bolt connection. One end of another steel rod is inserted into the fifth steel truss interface 73 and fixedly connected therein, for example, by fixed bolt connection. The V-shaped support 7 is suitable for fixedly connecting two steel rods.

[0043] In an embodiment of the present invention, the thickness of the top plate 1 in the area where the first boss 2 is located is 550 mm - 650 mm, such as 550 mm, 600 mm, 650 mm, etc. The thickness of the top plate 1 in the area outside the first boss 2 is 450 mm - 550 mm, such as 450 mm, 500 mm, 550 mm, etc. The thickness of the bottom plate 3 in the area where the second boss 4 is located is 750 mm - 850 mm, such as 750 mm, 800 mm, 850 mm. The thickness of the bottom plate 3 in the area outside the second boss 4 is 1050 mm - 1150 mm, such as 1050 mm, 1100 mm, 1150 mm, so that the subgrade structure meets the required strength requirements.

[0044] In this embodiment, the slopes of the first inclination angle θ and the second inclination angle β are 1:4, further optimizing the load transfer capacity of the overall subgrade structure.

[0045] In some embodiments, the top plate 1, the bottom plate 3, the steel truss 5 and the supports are all prefabricated components, and only need to be assembled one by one at the construction site, which is convenient for on-site construction, simplifies the process flow and controls the product quality. The construction time of casting concrete on-site is omitted, which has the advantages of saving the construction period and reducing costs, and is also convenient for operation and maintenance.

[0046] In some embodiments, the top plate 1 and the bottom plate 3 are prefabricated in accordance with the "Code for Design of Concrete Structures". The steel bar models and layout forms are configured according to requirements to make the structure meet the requirements of the ultimate limit state of cross-section bearing capacity and the normal use limit state. During the prefabrication process, key parameters such as water-cement ratio, cement strength, and initial setting time are strictly controlled to ensure that the structural strength meets the design requirements. After pouring, relevant quality inspections are carried out to facilitate the standardization and unification of the construction and installation links. At the same time, the combined structure of the top plate 1 and the bottom plate 3 made of reinforced concrete makes the subgrade structure have stronger bearing capacity, higher force transmission efficiency, and a more stable structural framework.

[0047] In some embodiments, the top end of the steel truss 5 is detachably connected to the corresponding support; and / or, the bottom end of the steel truss 5 is detachably connected to the corresponding support, which is convenient for quick installation during construction and shortens the construction period. In addition, when a certain steel rod in the steel truss 5 is damaged and needs to be replaced, only the steel truss 5 needs to be removed from the corresponding support, and then a new steel rod can be replaced, which simplifies the maintenance and repair process during later use and reduces the workload.

[0048] In some embodiments, the top plate 1 is detachably connected to the corresponding support; and / or, the bottom plate 3 is detachably connected to the corresponding support, which is convenient for quick installation during construction and shortens the construction period. In addition, when a certain support is damaged and needs to be replaced, only the corresponding support needs to be removed, and then a new support can be replaced, which simplifies the maintenance and repair process during later use and reduces the workload.

[0049] In some embodiments, the steel truss 5 can adopt a square or I-shaped standard section with a side length of 300 - 400 mm, such as 300 mm, 350 mm, 400 mm. Using steel with a standard section to form the steel truss 5 can reduce costs and facilitate procurement.

[0050] In an embodiment of the present invention, in order to facilitate the docking of the subgrade structure with the bridge box girder, the transverse width of the top plate 1 can be set to 12.6 m, and the transverse width of the bottom plate 3 can be set to 8 m.

[0051] An embodiment of the present application also provides a ballastless track, which includes the steel truss assembled double-track subgrade structure of any one of the foregoing embodiments, as well as a track slab foundation 9, a track slab 10 and a rail 11. The track slab foundation 9, the track slab 10 and the rail 11 are sequentially arranged from bottom to top on the top surface of the top plate 1.

[0052] The various embodiments / implementations provided in this application can be combined with each other without contradiction.

[0053] The foregoing are only the preferred embodiments of this application and are not intended to limit this application. For those skilled in the art, various modifications and variations can be made to the embodiments of this application. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of this application shall be included within the protection scope of this application.

Claims

1. A double-track ballastless track steel truss assembled subgrade structure, characterized in that: The subgrade structure includes a top plate, a bottom plate, at least two steel trusses, and a plurality of bearings. The steel trusses are arranged at intervals along the width direction of the subgrade structure and are supported between the top plate and the bottom plate. The width of the top plate is greater than that of the bottom plate, and the two are parallel and centered. A part of the bearings are fixedly installed on the bottom side of the top plate and are fixedly connected to the top ends of the steel trusses, and another part of the bearings are fixedly installed on the top side of the bottom plate and are fixedly connected to the bottom ends of the steel trusses. The top plate, the bottom plate, the steel trusses, and the bearings are all prefabricated components. The top end of the steel truss is detachably connected to the corresponding bearing, and the bottom end of the steel truss is detachably connected to the corresponding bearing; the top plate is detachably connected to the corresponding bearing, and the bottom plate is detachably connected to the corresponding bearing. A first boss is provided on the bottom side of the top plate, and a first bearing installation surface is provided on the first boss. The projection of the first bearing installation surface on the cross-section in the width direction of the subgrade structure is inclined to the horizontal direction, and the formed inclination angle is the first inclination angle. The bearings located on the bottom side of the top plate are fixedly installed on the first bearing installation surface; a second boss is provided on the top side of the bottom plate, and a second bearing installation surface is provided on the second boss. The projection of the second bearing installation surface on the cross-section in the width direction of the subgrade structure is inclined to the horizontal direction, and the formed inclination angle is the second inclination angle. The bearings located on the top side of the bottom plate are fixedly installed on the second bearing installation surface, and the slopes of the first inclination angle and the second inclination angle are equal.

2. The assembled double-track roadbed structure of steel truss for ballastless track according to claim 1, characterized in that: The steel trusses are arranged in pairs along the width direction of the subgrade structure, and the distance between the positions where the two paired steel trusses are connected to the top plate is greater than the distance between the positions where they are connected to the bottom plate.

3. The steel truss prefabricated double-track subgrade structure of the ballastless track according to claim 1, characterized in that: The steel trusses are perpendicular to the first bearing installation surface and the second bearing installation surface.

4. The steel truss assembled double-track subgrade structure of the ballastless track according to claim 1, characterized in that: The slope of the first inclination angle is 1:4; and / or, the slope of the second inclination angle is 1:

4.

5. The steel truss assembled double-track subgrade structure of the ballastless track according to claim 1, characterized in that: The thickness of the top plate in the area where the first boss is located is 550 mm - 650 mm, and the thickness of the top plate in the area outside the first boss is 450 mm - 550 mm.

6. The assembled double-track roadbed structure of steel truss for ballastless track according to claim 1, characterized in that: The thickness of the bottom plate in the area where the second boss is located is 750 mm - 850 mm, and the thickness of the bottom plate in the area outside the second boss is 1050 mm - 1150 mm.

7. A ballastless track, characterized in that: It includes the steel truss assembled double-track subgrade structure of the ballastless track according to any one of claims 1 to 6 above, as well as a track slab foundation, a track slab, and rails. The track slab foundation, the track slab, and the rails are sequentially arranged from bottom to top on the top surface of the top plate.

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